1. Field of the Invention
The present invention relates to an information processor, and more particularly to an information processor that is provided with a serial controller for controlling serial data transfer.
2. Description of the Related Art
As a countermeasure against faults, information processors often feature a construction that is provided with a fault analysis means or reserve devices in addition to normally required devices. For example, an improvement in the reliability as an information processor can be obtained by providing a duplex structure for the CPU, memory unit, or memory controller for controlling data transfer between the CPU and memory unit and then switching to the reserve standby system in the event of a fault in the working system that is used in normal operation.
As another example of an information processor having greater reliability, one known construction is provided with a service processor for collecting information such as fault detection information or log-out data at the time that a fault occurs and then analyzing the site of the fault.
Of the information processors of this type in the prior art, constructions in which the operation of the CPU is controlled by a serial console are still prone to the problem that, if the serial console is included at the point of incidence of a fault, messages or data that are issued from that serial console may be lost despite the duplex configuration of the CPU or memory unit.
In addition, if a fault occurs at a serial controller that is provided in a serial console, this serial controller being the I/O interface between the CPU and input/output device, this fault may constitute an SPoF (Single Point of Failure) and may halt the operation of the entire information processor.